Electronic devices such as servers include electronic components that are connected to a power supply. Servers generate an enormous amount of heat due to the operation of internal electronic devices such as controllers, processors, and memory. Overheating from the inefficient removal of such heat has the potential to shut down or impede the operation of such devices. Thus, servers are designed to rely on air flow through the interior of the device to carry away heat generated from electronic components. Servers often include various heat sinks that are attached to the electronic components such as processing units. Heat sinks are typically composed of thermally conductive material. Heat sinks absorb the heat from the electronic components, thus transferring the heat away from the components. The heat from heat sinks must be vented away from the server. Airflow to vent away such heat is often generated by a fan system that accelerates airflow through the components and the heat sink. The generated airflow thus carries collected heat away from the components and the heat sink.
In devices such as servers, the system power is limited by the thermal design for cooling such components. Thus, the operating velocity of such devices is constrained by the thermal design, as components must sometimes be run at lower velocities so they don't overheat. By the principles of energy conversation, the power limitation of a fan cooled device is proportional to the air quantity flowing through the device. The greater the air quantity, the more air flow is available for cooling, and therefore the power, (and therefore performance) of the system may be increased. High system power allows higher power to components such as a CPU. Higher power allows more efficient operation of the CPU and thus results in increased calculation speed.
FIG. 1 is a perspective view of a traditional chassis design of a half node server 10. The server 10 includes two CPUs 12 and 14 in “shadow placement” in a chassis 20. The CPUs 12 and 14 are mounted on heat sinks (not shown) that conduct heat generated by the CPUs 12 and 14. The chassis 20 includes two side walls 22 and 24. The side walls 22 and 24 define a front opening 26 and a back wall 28. The back wall 28 mounts two system cooling fans 30 and 32. Air passes through from the front opening 26 of the chassis 20 to the back wall 28. In FIG. 1, air flow is generated by the two system fans 30 and 32.
The front of the chassis 20 includes a space 40 for different component cards, such as PCIE compatible cards, that may be inserted in slots (not shown). In this example, the CPUs 12 and 14 are arranged in tandem between the side walls 22 and 24. The chassis 20 holds double data rate (DDR) SRAM memory devices 42 and 44 in proximity to the CPUs 12 and 14. The SRAM memory devices 42 and 44 are arranged in slots to allow openings between them for air to flow through the chassis 20. Two large capacity memory devices 46 and 48 are mounted in proximity to the fans 30 and 32. In this example, the memory devices 46 and 48 may be hard disk drives or solid state drives.
Heat is generated by the operation of the CPUs 12 and 14, the SRAM memory devices 42 and 44, and the memory devices 46 and 48. Air flow generated by the fans 30 and 32 is used to cool these devices. The cooling efficiency depends on the air quantity moving through the chassis 20. In traditional chassis designs such as that in FIG. 1, there are two ways to increase air quantity and thus cooling. One way is to increase the velocity of the fans 30 and 32, thus increasing air flow. Another way is to reduce the number of components contained in the chassis 20, thus reducing system air impedance. However, increasing fan velocity is not effective when the fan is placed nearby components such as the hard disk drives 46 and 48. Such barriers in front of the fan cause more vortices near fan inlet portion. Thus, when the fan speed is increased, the vortices will be close to the fan inlet and decrease fan efficiency. Further, removal of components, such as one of memory devices 46 or 48 or a CPU 12 or 14, reduces the capabilities of the device.
Thus, there is a need for a computer device chassis that maximizes the quantity of air flow for cooling components. There is another need for nozzle structures to inject higher velocity air in the front of a computer device chassis to assist in cooling. There is also a need for a chassis design that allows the use of high pressure fans and ducts to generate air jets.